A dispenser for an instant beverage vending machine is designed to receive the water entering said dispenser coming from the boiler and provide the exit for said water towards an outlet channel, which is determined depending on the beverage selected by the user, for example: coffee, coffee with milk, chamomile infusions, tea, chocolate, etc.
According to what is currently known, in order to cause the water to exit through the adequate channel, dispensers use one or several electrovalves assembled over the body of the boiler, connected to said boiler or as a satellite to it, as is described in Spanish patent request P200931021, by JOFEMAR.
In said request P200931021, the opening and closing of said electrovalves is made through the excitation of magnetic induction coils that overcome the force of a spring which is in charge of guaranteeing the closing of the electrovalves when said electrovalves are not excited and of holding the pressure generated inside the boiler due to the water heating. The electrovalves of these systems may have two or three lines but, in any of the two cases, they have several functionality problems, due to the lime built up as a consequence of heating the water, as well as coffee grounds reaching said electrovalves, occasionally preventing the normal operation of said valves due to the placement of said particles among the closing surfaces of the electrovalves, causing the system not to be watertight, contrary to how it should be.
In other occasions, these particles are deposited in the opposite side of the closing area, preventing the movement of the mobile induction core and thus the opening of said electrovalve in situations when it should be open.
The patent document US 2010077927 discloses a water dispenser for instant beverages vending machines comprising:    a first hot water inlet pipe towards the dispenser;    a second pipe provided with a first inlet and also provided with several second outlets to allow water to exit said second pipe towards two beverage selection channels;    a rod arranged inside the second pipe and which is longitudinally movable along said second pipe by action of actuation means, said rod being provided with at least one first narrowing arranged in an intermediate area;    water tightness means, arranged on both sides of a second outlet to prevent the circulation of water between the rod and the inner surface of the second pipe, wherein the actuation means are adapted to provide the stopping force to the rod, in at least one first position and a second position, where the first position of the narrowing of the rod is located entirely between the water tightness means corresponding to two consecutive outlets, and in the second position, at least a part of the narrowing is housed between some water tightness means and their corresponding second outlet, so that the water may circulate between the rod and the water tightness means, to access the corresponding second outlet and leave the second pipe towards a channel corresponding to a selected drink.
In summary, there is uncertainty in these systems, in the sense that there are no guarantees as to whether the opening or closure condition of the electrovalves corresponds with what is theoretically assumed depending on the selection made.